Evaluation of osseous regeneration, using the low-power laserterapy in rats

Introduction:

Rapid maxillary expansion is one of the most used therapies in the orthodontic practice for the posterior crossbite correction. The relapsed after expansion treatment required a contention device to guarantee a successful therapy. The neoformation suture and the maxilla could be maintained in the new position for a minimum period to get the stability. It could become a benefit to accelerate the osseous regeneration in the medline suture after expansion to reduce the retention period of contention. The use of laser in the osseous regeneration is justified for the possibility in decreasing the retention period to guarantee a greater stability after treatment.

Aim:

Was to investigate the low power laser effect with different power in the osseous regeneration in the midline palatal suture area.

Method:

Twenty male rats (Wistar) of 45 days old were used. The animals were divided into five groups of four rats in each: group 1 – Non irradiation and non expansion; group 2 – Non irradiation and expansion; group 3 – expansion and one dose of irradiation 4J/cm2; group 4 – expansion and one dose of irradiation 8 J/cm2;: and group 5 - expansion and two dose of irradiation 4 J/cm2. The irradiation groups received the doses in the first day of the study and the second irradiation was two days after the first time. The irradiation was done in the palatal suture midline.

Results:

Group 1 showed an osseous normal development in the midline palatal suture. Group 2 showed an osseous regeneration with oesteoblasts. The expansion and laser therapy groups (group 3, 4 and 5) showed similar results but with some particularities.

Conclusions:

The laser therapy has a discreet effect on the osseous regeneration in the midline palatal suture in rats and the experimental group showed less inflammation in the suture area but not statistically significance.